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United States · MT · Deer Lodge

Montana State Prison

Low
Verified 29 May 2026
Fresh · 1d ago

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Photograph of Montana State Prison

Gallery

From Wikimedia Commons (CC-BY-SA where not otherwise stated).

  • CB1OMP.jpg

    Photo by Tanankyo via Wikimedia Commons (Public domain)

  • Montana State Prison c. 1940s in Deer Lodge (11145680993).jpg

    Photo by simpleinsomnia via Wikimedia Commons (CC BY 2.0)

  • MT - DOC.png

    Photo by SGT141 via Wikimedia Commons (Public domain)

  • Old Montana State prison, Deer Lodge 06.jpg

    Photo by Montanabw via Wikimedia Commons (CC BY-SA 3.0)

  • Old Montana State prison, Deer Lodge 07.jpg

    Photo by Montanabw via Wikimedia Commons (CC BY-SA 3.0)

  • Old Montana State Prison, Deer Lodge, MT (9982582095).jpg

    Photo by simpleinsomnia via Wikimedia Commons (CC BY 2.0)

  • OldMTPrisonT7CB1.jpg

    Photo by Tanankyo via Wikimedia Commons (Public domain)

  • OMPadminCB1.jpg

    Photo by Tanankyo via Wikimedia Commons (Public domain)

Background

The Montana State Prison is an American men's correctional facility of the Montana Department of Corrections in unincorporated Powell County, Montana, about 3.5 miles (5.6 km) west of Deer Lodge. The current facility was constructed between 1974 and 1979 in response to the continued degeneration of the original facility located in downtown Deer Lodge. The "Old Prison" (46°23′33″N 112°44′10″W) served as the Montana Territorial Prison from its creation in 1871 until Montana achieved statehood in 1889, then continued as the primary penal institution for the State of Montana until 1979. Throughout the prison's history, the institution was plagued with constant overcrowding, insufficient funds, and antiquated facilities. The administration of Warden Frank Conley from 1890 to 1921 proved the exception to this rule, as Warden Conley instituted extensive inmate labor projects that kept many inmates at work constructing the prison buildings and walls as well as providing various state and community services like road building, logging, and ranching.

Source: Wikipedia article lead, CC-BY-SA.

Capacity

Current population

Occupancy

Year opened

Operational

Facility profile

Operator

Montana Department of Corrections

Population held

Mixed/unknown

Opened

Region

MT

Security level

Death-row facility

No

Conditions

No conditions summary available yet.

Visiting

No visiting information available.

Mailing

No mailing information available.

Practical info

Contact the operator's website for inmate-specific procedures.

Known issues

No major issues documented in our database.

Contact & address

400 Conley Lake Road, Deer Lodge 59722

Conditions Risk Score

Derived signal — not a judgement. How it's calculated

Insufficient data
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Data completeness

38%

How many of our profile fields are populated. We surface this so families and researchers know the limits.

Sources